#include<iostream>
using namespace std;

template <class T1,class T2>
class app
{
    friend void printfff(app<int,char> &ob);
    private:
        T1 a;
        T2 b;
    public:
        app(){};
        app(T1 a,T2 b)
        {
            this->a=a;
            this->b=b;
        }
        void show();
};

void printfff(app<int,char> &ob)  //普通函数做友元，直接说明类型就行
{
    cout<<ob.a<<"  "<<ob.b<<endl;
}
int main()
{
    app<int,char> ob(10,'a');  
    printfff(ob);
    system("pause");
    return 0;
}